This invention relates in general to a female electrical terminal. In particular, this invention relates to a two piece clean body female electrical terminal that includes a spring that biases the contact arms inwardly.
A pin or lance style electrical connector includes a male terminal, having an elongated lance made of a conductive material, and a corresponding female terminal, having a plurality of contact arms made of a conductive material. To mate the male terminal and the female terminal, the lance is inserted between the contact arms and pushes them apart. The contact arms press against the lance in order to maintain an electrical connection between the male terminal and the female terminal.
The force with which the contact arms engage the lance determines a terminal retention force, which is the amount of force that is needed to pull the male terminal out of engagement with the female terminal. In some instances, it is desirable to increase the terminal retention force. This may be desirable, for example, when the female terminal is expected to heat up during use, which will cause the conductive material to become softer. As the material softens, the terminal retention force may decrease. This reduction in the terminal retention force could lead to a reduced reliability in the electrical contact between the male terminal and the female terminal.
The terminal retention force can be increased by adding a spring element to the female terminal to create a two-piece female connector. An example of such a two-piece female terminal is disclosed in U.S. Pat. No. 7,892,050, the disclosure of which is incorporated herein by reference. The spring element is typically made of a material that has better spring characteristics than the conductive material, at least at higher temperatures. A typical two-piece female connector includes a contact piece made of copper or aluminum that includes one or more pairs of forwardly extending contact arms. A spring piece made of stainless steel includes forwardly extending spring arms that press the contact arms inwardly toward each other.
Electrical terminals are used in a variety of applications and in a variety of different environments. In order to protect electrical terminals from water or other contaminants, various types of seals may be used. One type of seal commonly used with electrical terminals is a mat seal used in an electrical connector. Electrical connectors are housings that hold one or more electrical terminals, and corresponding connectors are mated to mate the held terminals. A mat seal is a mat of elastomeric material that is held in the electrical connector. The female terminal is positioned adjacent to the mat, and the mat includes openings that the male lance extends through in order to mate with the female terminal.
The previously described two-piece female terminal is typically not used in combination with a mat seal. Rather, a clean body female terminal is typically used in combination with a mat seal. An example of a clean body female terminal is disclosed in U.S. Pat. No. 4,834,681, the disclosure of which is also incorporated herein by reference. The clean body female terminal includes a box-shaped housing with contact arms that are located within the box. When the male lance mates with the clean body female terminal, it enters from the front of the box and extends into the box between the contact arms.
The clean body female terminal offers some advantages over the two-piece female terminal. The outer shape of the clean body female terminal is the box structure, which provides a stable shape that is able to mate with the mat seal. Additionally, the contact arms extend back and into the box, which means the ends of the contact arms are not in a position to accidentally engage with the mat seal and damage the seal. Also, because the contact arms are located within the box, the box protects the contact arms from damage during handling and assembly. It would be advantageous to have a female terminal that provides the advantages of the clean body female terminal, while also providing the advantages of the two-piece terminal.